The military-industrial scientific research system of the academic master.

Although he had anticipated the result, Sun Cong still couldn't help feeling a little regretful when the time came.

The solution that the 601 Institute initially favored was a three-wing solution, the focus of which was to achieve greater maneuverability with a relatively weak power level.

But for well-known reasons, about a few years ago, the general premise of "weaker power level" underwent some small changes, so they also shifted their focus to conventional layouts and semi-tailless layouts.

This time, we brought both plans and planned to decide which one to use based on the situation on site.

Therefore, when Chang Haonan took out the indicator of WS-10G, they already had the idea of ​​competing with a semi-tailless layout.

Coupled with the subsequent targeted remarks from Institute 611, the delegation finally reached a consensus.

After all, they also took into account that Academician Chang was able to develop a quasi-fourth-generation turbofan 10 in less than five years, so it seems reasonable for him to develop a thrust vectoring technology in less than five years now.

But success also brings failure.

The last glimmer of hope for this plan was extinguished with Chang Haonan's statement.

Correspondingly, Yang Wei, who was sitting opposite him, let out a long sigh and couldn't help but reveal a relaxed expression.

In fact, until recently, even within the 611 Institute, there were some different opinions on whether to continue the J-10's wing configuration in the design of the fourth-generation fighter.

Especially considering the rapid progress of the domestic aero-engine industry, it seems that it is not impossible to come up with a model that can compete with the F10 in about 119 years.

In this case, directly replicating an F22 is obviously the option with the least risk.

As for the transition period in the middle, the WS-10B, which has already passed the test on the J-10, can be used.

But on the one hand, 601 lacks accumulation in conventional layout, and its mediocre plans are difficult to stand out within the group.

On the other hand, Yang Wei himself does not want to simply follow the Americans.

The opening remarks he just made were actually spoken to himself as well as to other people.

Fortunately, the final result is in line with expectations...

……

After all, the Aviation Industry Corporation of China is an integrated entity. Although the subordinate units may have differences in technical routes, generally speaking, once the direction is determined, they can still work together.

For example, the 611 Institute had no experience in designing twin-engine heavy aircraft in the past, so although it had the initiative in design layout, it still needed help from other brother units in terms of structure.

Therefore, the content of the rest of the meeting was basically to communicate with representatives of the Air Force Equipment Research Institute such as Lu Guang, and to continue to deepen some details based on the canard + large delta wing plan.

In fact, although Chang Haonan has worked as a senior executive in the Aviation Power Group for several years, he started out in aircraft design after all.

So even in the second half of the meeting, there were still people asking him questions from time to time.

But in the face of these questions, Chang Haonan basically only gave the most basic answers, and did not expand on too much content like he did just now -

It was not to avoid suspicion in business, but he was still thinking about the semi-tailless plan proposed by 601.

After all, from the perspective of equipment habits, for the sake of risk sharing and business balance, the air forces of major powers generally will not be equipped with only a single type of main fighter.

From a technical point of view, the canard + large delta wing layout is not particularly suitable for shipboard use due to its flight characteristics during takeoff and landing.

This can be verified from the technical data of Rafale M in his hands.

More importantly, the semi-tailless layout just fits in with a certain important new technology that Chang Haonan is preparing to develop in the next stage...

Therefore, taking advantage of the lunch break of the meeting, Chang Haonan took the initiative to find Sun Cong, who was still in a low mood.

Although the two had never worked together directly, Chang Haonan had worked at the 601 Institute for quite a long time and had received the "Operation Bat Hunting" commemorative medal together with the latter, so they could be considered old acquaintances.

Due to limited time, after a brief greeting, Chang Haonan went straight to the point:

"Mr. Sun, I was just discussing the matter at the meeting just now. In fact, I am quite interested in the semi-tailless layout of our 601 Institute..."

Of course Sun Cong knew that the other party was not targeting him.

But as a human being, it is inevitable that you will have emotions at times like this.

Of course, Chang Haonan is now an academician, so it is impossible for him to really show any dissatisfaction.

But I still don't want to talk about this sad thing.

So I immediately prepared to change the subject:

"I understand, Academician Chang... it's all in the past, there's no need to mention it anymore..."

But just when he was halfway through his speech, he was interrupted by Chang Haonan:

"I'm not being polite, I'm really interested in this plan."

As he spoke, he pointed to the PPT that was still on the computer screen next to him.

Sun Cong was silent for a moment, then he sighed heavily, and still couldn't help but speak:

"Academician Chang, if you really take the lead in developing a vector propulsion technology, can you really not overcome the lifespan issue?"

Obviously, he still felt unwilling in his heart.

Chang Haonan did not answer the question directly, but smiled and whispered:

"Actually, I came to you this time just to discuss this matter in detail..."

Hearing this, a look of astonishment flashed across Sun Cong's face for a moment.

Then he looked hopeful again.

"We are currently testing several types of vector nozzles on the ground, including those already in use by the United States and Russia. Whether it is a guide vane type, a convergent adjustment plate type, a dual pitch type, or even a swing type used in rocket engines, they are all mechanical thrust vector nozzles."

"Although the principle of adjusting the thrust direction through mechanical structure is simple, the control mechanism is complex, cooling and sealing are difficult, and the extra weight is heavy... Moreover, hundreds of tiny moving parts are added out of thin air. No matter how advanced the technology is, the reliability and life will definitely be affected. This is determined by engineering principles..."

Chang Haonan paused for a moment when he spoke here.

Sun Cong also nodded to show that he understood.

"So I have been thinking about developing an aerodynamic vector nozzle with a fixed geometry, so as to avoid the performance loss caused by a complex mechanical structure."

Now, Sun Cong was a little confused...

"A vector nozzle with a fixed geometry?"

He frowned, and even for a moment wondered if he had heard it wrong.

The core function of the vector nozzle is to change the thrust direction.

But the geometry must be fixed...

It gives a sense of déjà vu like "zooming in and then shrinking a little bit" or "colorful black".

Chang Haonan also knew that his statement was a bit strange, so he quickly explained:

"You should know that the ejector nozzle used on the old turbofan 10 is to adjust the throat area of ​​the nozzle by injecting secondary flow at the throat of the nozzle, right?"

The old WS-10 he mentioned was the version that had been shelved before he took over.

Sun Cong nodded subconsciously at first, and then showed an expression of enlightenment: "So that's it":

"You mean, injecting secondary flow into the nozzle in an asymmetric manner, so as to control the direction of thrust generation through the secondary flow effect?"

"That's right, that's why it's called an aerodynamic vector nozzle."

Chang Haonan looked at the layout rendering of the semi-tailless layout again:

"But this technical route requires a very sophisticated engine electronic control system and a much larger engine air intake volume than the conventional one, so a completely new aviation platform is needed to fully exert the performance advantages..."

"I don't know... Mr. Sun, what are your intentions?"